There is no chemical bond and homogeneous acid decomposition reaction in the preparation of oleanolic acid. Therefore, the bioavailability of oleanolic acid is greatly improved. Further, according to the prodrug theory such as Jiang Zhaohui, the structural modification of oleanolic acid is carried out, and the dicarboxylic acid CS Oh formed by monoester is converted into disodium salt, which is a water-soluble prodrug disodium salt, oleanolic acid It has been synthesized into disodium succinate, disodium oleanolate, Monomaleate, protodisodium cyclohexaneoleanolate, disodium oleanolate and disodium phthalate. The preliminary pharmacological experiment results show that the protective effect of sodium on experimental liver injury is different from that of oleanolic acid. However, high dose of oleanolic acid will not aggravate the liver injury, and the side effects may be changed from the dosage form of oleanolic acid to improve the bioavailability of oleanolic acid and improve the curative effect.